Solar sails sound like something that’s strictly science fiction but they’ve had a surprising amount of real world success over the past 5 years. Back in 2010 Japan launched their IKAROS craft, an ambitious project that had its sights set on a fully solar sail powered mission to Venus which it successfully completed in December of the same year. Nanosail-D2 (D1 was lost when the Falcon rocket carrying it failed to reach orbit) followed shortly afterwards and, whilst it had some issues deploying from its parent satellite, eventually managed to deploy and stay in orbit for some time. The most recent mission, headed up by the Planetary Society who took over the Nanosail project from NASA, called LightSail-A announced that they had successfully deployed their sail which bodes well for their future missions.
Whilst this isn’t exactly new territory for solar sails as a technology it is a rather important validation of the technological platform that the Planetary Society wants to use going forward. LightSail-A was built on a three unit cubesat platform with one unit dedicated to the core electronics platform and the other two holding the solar sail. It’s essentially another version of the Nanosail-D type craft that NASA launched when they were in charge of the program although I’m sure there’s some fundamental differences under the hood. What’s really interesting about LightSail-A though is that it’s entirely funded by the Planetary Society through their member dues and a wildly successful Kickstarter campaign, raising the requisite $1.8 million to get their craft into orbit.
It hasn’t been smooth sailing for this little craft however, something which seems to be par for the course with solar sail projects. Two days after launch LightSail-A fell out of contact with earth, rendering it unable to deploy its sail. All hopes were then pinned on LightSail-A rebooting itself which it did just over a week later. Just a few days after that however an issue with the battery system, which had failed to charge after the solar panels had deployed, knocked the craft out of communication again. 4 days ago however contact was reestablished and, just one short day afterwards LightSail-A confirmed that it had deployed its sails. Today the Planetary Society released the first image captured from LightSail-A (shown above), confirming that the sails had been deployed.
The amount of time that the craft has left up in orbit is anyone’s guess as the original mission duration was planned for two to ten days after the sail had been deployed. The altitude of LightSail-A’s orbit means that it can’t be used to test the propulsion capabilities as the atmospheric drag is far greater than any thrust that the sail can generate. The next week or so will give the Planetary Society enough time to shake down the rest of the systems, hopefully working out any further kinks before they attempt their next mission, currently planned for sometime next year.
It might not be the most revolutionary nor sexy of space missions however the fact that this happened on the back of support from the public is what makes LightSail-A’s accomplishments significant. Solar sails have the potential to revolutionize the way our spacecraft access deep space, enabling faster and more efficient missions to other celestial bodies within our solar system. We may be a decade or so away from seeing it being adapted in earnest but without missions like LightSail-A we’d be waiting for much, much longer.
I won’t lie to you it’s been hard to be motivated about much with Canberra’s climate the way it is at the moment. Waking up to a backyard covered in frost, whilst beautiful in its own way, is a sure way to make me yearn for the comforts of my warm bed forsaking any work commitments. Despite that though I’ve had quite a few productive weekends huddle away from the icy bite of the outdoors and I’ve come to notice a lovely trend in the headlines gracing my feed reader: There’s been some tangible progress in almost all areas of space exploration and that never fails to make me extremely happy.
The first bit of news comes from Virgin Galactic. It’s been a while since we last heard from them after the maiden flightof SpaceShipTwo, almost 4 months to the day. Still that doesn’t mean that progress hasn’t been made and the announcement came out just recently that they had performed their first fully crewed flight:
A private suborbital spaceship built for the space tourism firm Virgin Galactic made its first flight with a crew onboard Thursday as it soared over California’s Mojave Desert beneath its enormous mothership.
The commercial spaceliner – called VSS Enterprise, one of the company’s fleet of SpaceShipTwo spacecraft– did not try to reach space in the test flight. Instead, it stayed firmly attached to its WhiteKnightTwo VMS Eve mothership.
The two crewmembers riding onboard VSS Enterprise evaluated all of the spacecraft’s systems and functions during the 6-hour, 12-minute flight, Virgin Galactic officials said in a statement. In addition, automated sensors and ground crews conducted thorough vehicle systems tests.
Now that might not seem like much on the surface but it is in fact quite a giant step forward for Virgin Galactic and the Scaled Composites guys. The two craft soared to over 15KMs high, that’s nearly double the height that most passenger jets fly at. To put that in perspective that means that many of the life support components of the craft have been verified as at that altitude you wouldn’t last long without functioning life support, and definitely not the 6 hours they were up there for. Completing these tests brings the SpaceShipTwo dream that much closer to reality and with the commercial flights scheduled for 2011 I’m sure we’ll see a powered test flight before the year is out.
The second came in the form of my current space crush, SpaceX. It’s been little over a month since their Falcon 9 rocket soaredinto the history books and gave us Australians a lightshow to rival those that our Nordic cousins had experienced. This week brings news that so soon after their last launch they’re already gearing up for the next one, with the parts for a new Falcon 9 arriving at Cape Caranaveral:
Six weeks after the first Falcon 9 rocketed into orbit, pieces of the second launcher have begun arriving at Cape Canaveral for a shakedown flight of SpaceX’s Dragon capsule in September, according to the company’s top executive.
The Falcon 9 first stage pulled into Cape Canaveral Thursday after a truck ride from SpaceX’s test site in central Texas.
The stage was placed inside the company’s rocket assembly hangar at launch pad 40. Officials said they untarped the rocket and completed initial inspections Thursday night.
Engineers plan more testing over the next several weeks to make sure the stage and its nine Merlin engines are ready for flight.
Again it might not seem like a lot but it’s a testament to the fact that SpaceX is quite serious about being a fully fledged orbital launch company competing with the giants of Boeing and Lockheed who’ve dominated this sector for decades. Additionally it shows that many of the processes that are required for them to be able to churn out a respectable number of rockets are in place and working beautifully, rather than the recent launch being nothing than a one off prototype ala Ares 1-X. The next flight, which looks to be on track for a launch towards the end of this year, will fly the first fully functional Dragon capsule complete with full avionics, life support and most importantly the heat shield for re-entry. The current specs of the Dragon capsule have it rated to be able to return to Earth from missions to the Moon and Mars, something that suprised the entire space community. I have no doubt that it is quite capable of this and it gives me the feeling that Elon Musk might have dreams of going far beyond LEO with SpaceX. I’m getting all giddy just thinking about it.
The last, and most impressive, is something that any science fiction fan will tell you is possible but until just recently it wasn’t actually used as the primary means of propelling a space craft. IKAROS, a craft I wrote about 2 months ago, unfurled its sails and successfully used the sun’s radiation pressure to propel the craft through space:
We’ve been following the progress of the Japanese spaceship IKAROS — the first to unfurl a solar sail in deep space. Today, the ship made the only first that really matters: it caught the sun’s rays with its 3,000 square-foot sail and successfully used the energy to speed its way through space.
Each photon of light exerts 0.0002 pounds of pressure on the 3,000-square-foot sail, and one after another they succeeded in propelling the nearly 700-pound drone. Japanese scientists expect to be able to control IKAROS’s velocity by adjusting the angle at which incoming radiation strikes the sails. For a full technical explanation of how the drone is moving, check out the Japanese space agency JAXA’s press release.
Solar sail technology is important because it allows spacecraft to travel without fuel, which could allow them to penetrate ever deeper into space.
This is probably one of the biggest advances in space technology we’ve seen in quite a long time. Solar sails have the potential to propel craft to speeds far beyond any of our current craft and rivalling even some of the theoretical nuclear craft. Of course there is still a long way to go until this can be used for larger craft (IKAROS is ~300kg) but the demonstration verifies that several key technologies function as expected and produce the required results. This success means there’s a good chance that the proposed larger solar sail craft will get the funding it needs to bring it into reality. I can’t wait to see what kinds of interesting missions solar sails will make possible.
It’s been a while since I’ve been able to write one of these starry eyed posts about space and I’ll be honest it feels good to be able to do it. Space is one of those things that I always find myself losing hours on and being able to share some of that wonder with an audience always gives me such a great feeling of accomplishment. I know one day, thanks to the achievements outlined here, that I’ll be able to venture into space and share in the impressive achievement that is humanity reaching out into space.
Interesting, if you turn the clock back a year it seems that I wrote a very similar post to this one, coincidence? Most likely 😉
Solar sails are one of those things that a lot of people have heard about but no one really seems to know too much about. I guess I owe George Lucas and James Cameron a debt of gratitude for this phenomenon as both their sci-fi block busters feature the technology in one way or another. Still for all the postulating that has been done in the world of sci-fi that appears to well grounded in real world science you’d be hard pressed to actually find any actual craft that have launched and demonstrated the feasibility of solar sail technology. It would seem that something akin to the Mars Curse plagues the potentially revolutionary space propulsion that is solar sails.
That’s not for lack of trying however and since the idea was first thought of way 1924 by Friedrich Zander there have been many attempts to prove that the concept works. For a solar sail to work it needs a large surface area to capture as much of the minute pressure that the sun exerts on everything around it. This poses a significant challenge to craft designers as anything large either means lots of mass or some kind of tricky deployment system. As with any space mission weight is at a premium so all solar sails to date have been extremely large and very thin (in the order of millionths of a meter) and therefore have some kind of complicated deployment mechanism. As anyone who has worked with aluminium foil (which by comparison is 0.2mm thick, almost 100,000 thicker ) before can attest such materials are inherently fragile and all successful solar sail missions so far have focused on actually getting themselves deployed, not on whether or not solar sails actually work.
That might seem a bit strange, especially considering the potential game changer that solar sails are, but it all comes down to its potential applications. Right now there’s really little commercial interest outside Low Earth Orbit and as such the only interest comes from potential scienctifical applications. With the technology as of yet still unproven solar sails won’t make it aboard any deep space missions just yet as there can be no guarantee that it will function as predicted. This hasn’t stopped people from looking into the technology though, with Japan being the latest nation to step up to the plate:
Though solar sail-powered crafts have been used before, Ikaros is the first to attempt to enter deep space. The craft’s 46-foot sails come equipped with solar cells thinner than a human hair. When solar particles hit the cells, they generate power for Ikaros. Mission controllers on the ground will steer the craft by adjusting the sails’ angles, ensuring optimal amounts of radiation are reaching the solar cells.
Ikaros’s pricetag is in the realm of $16 million dollars. And while it’s certainly an ambitious project, there are no guarantees the fuel-free space explorer will work. A rocket will transport Ikaros to space on May 18th, along with Japan’s first satellite to Venus. Stay tuned to see how Ikaros fares when the spacecraft finally gets its day in the sun.
IKAROS (ha! Science humour) is quite interesting for a number reasons. The first is that it is the first solar sail mission to be aimed squarely at deep space. It’s admirable because nearly every other mission thus far hasn’t given any thought to get past LEO or HEO, mostly because it would be easier and cheaper. Secondly they’ve taken the novel approach of converting sections of the sail into solar panels as well, which will provide a decent amount of juice for the craft. This further reduces the required weight of the craft (eliminating heavy batteries) which means they can cram a whole lot more science into this package. Secondly the entire project is being funded on what is to be considered a shoestring, a mere $16 million dollars. If this project is successful it will not only prove that solar sails are a viable propulsion method it will also show that they can be extremely cheap. There are countless deep space missions that could be achieved if such deep space propulsion was this cheap, so you can see why the space community is a buzz with excitement at this missions prospects.
Solar sails are one of those technologies that’s been firmly rooted in the world of sci-fi for decades and the prospect of them becoming real just gets me all kinds of excited. I feel that we’re all extremely fortunate to be on the cusp on the next revolution in human’s ability to travel to places we’ve never gone before. The day will come when humanity begins stretching our reach beyond our solar system and there would be nothing more amazing than to do that by sailing on the solar pressure waves of our very own star.